LF5895 25.4 mm Dia. CaF2 Negative Meniscus Lens; EFL=-75mm Uncoated

The LF5895 is a spherical lens from Thorlabs, featuring a concave-convex base shape and a circular geometry. With a diameter of 25.4 mm, this lens is designed for use in optical systems that require a negative meniscus lens. The lens's thickness at the edge is 8.5 mm, while its center thickness is 4 mm, providing a robust and stable platform for optical applications.

The effective focal length (EFL) of the LF5895 is -75 mm, making it suitable for use in systems that require a converging lens. The first radius of curvature (r1) is 30.8 mm, and the second radius (r2) is 14.8 mm, contributing to the lens's overall optical performance. The back focal length (bfl) is -72.2 mm, which should be considered when integrating this lens into an optical system.

The lens is made of Calcium Fluoride (CaF2), which has a Mal-1963 material ID. This material is known for its excellent transparency in the ultraviolet, visible, and near-infrared regions of the spectrum, making it an ideal choice for a wide range of optical applications. The lens is uncoated, which may affect its performance in certain applications, particularly those involving high-intensity light sources or extreme environmental conditions.

The LF5895 is designed for use at a wavelength of 4000 nm. This wavelength compatibility should be considered when selecting this lens for use in optical systems. The lens's shape is spherical, which is a common choice for many optical applications due to its simplicity and versatility.